Fuel cell stacks are used as an electrical power source in many applications. In particular, fuel cell stacks are proposed for use in automobiles to replace internal combustion engines. In typical applications, fuel cell stacks are provided in arrays of many individual fuel cells in order to provide high levels of electrical power. The complexity of fuel cell stacks which can have several hundred individual fuel cells necessitates that strategies and conditions for efficient testing be developed.
Accordingly, there is a need for fuel cell charging systems that can maintain a fuel cell stack at a voltage that is useful for performing a certain subset of diagnostic tests.